Researchers have created a soft robotic “finger” with an advanced sense of touch capable of conducting standard medical exams in a doctor’s office, including measuring a patient’s pulse and checking for unusual lumps.
A team from the University of Science and Technology of China has engineered a soft robotic “finger” that possesses a refined tactile ability, enabling it to perform common medical assessments such as taking a patient’s pulse and examining for abnormal lumps. The findings were released on October 9 in the journal Cell Reports Physical Science.
This innovative technology could facilitate the early detection of diseases like breast cancer, a time when treatment is often more effective. It also aims to help patients feel more comfortable during physical checkups, which can sometimes be awkward and invasive.
“With further improvements for greater efficiency, we envision that a skilled hand made of these fingers could function as a ‘Robodoctor’ in future healthcare settings, similar to a real doctor,” states Hongbo Wang, a sensing technology researcher and co-author of the study. “When integrated with machine learning, robotic examinations and diagnostics could be automated, which would be particularly advantageous in underdeveloped regions suffering from a lack of healthcare personnel.”
While there are rigid robotic fingers available, experts have expressed doubts regarding their suitability for the careful tasks demanded in a clinical environment. Concerns have been raised about potential safety hazards, such as the risk of damaging lumps during examinations. Recently, advancements in lightweight, safe, and affordable soft robotics have been made, enabling devices to mimic human hand movements more effectively. However, these devices have struggled to sense the intricate properties of the objects they touch like real fingers do.
“Despite significant advancements over the past decade, most soft fingers discussed in literature still fall short compared to human hands,” the authors mention, highlighting that robotic fingers have not yet been equipped to address ’real world’ situations.
To tackle this issue, the researchers devised a basic device featuring conductive fiber coils organized into two components – one coil wrapped around each air chamber in the device’s bending actuators (the sections that allow for movement) and a twisted liquid metal fiber positioned at the fingertip. By analyzing elements that influence the flow of electrical current in the device, the team was able to track the angle of the finger’s bending and the pressure at the fingertip in real time. This allows the device to discern an object’s characteristics as effectively as human touch.
For testing the device, the researchers initiated their experiment by lightly dragging a feather across its fingertip.
“The magnified view distinctly shows the change in resistance, demonstrating its impressive sensitivity to force,” the authors state.
Subsequently, they tapped and pressed the fingertip with a glass rod and repeatedly bent the finger, noting that the sensors accurately detected the type and amount of force applied. To evaluate the finger’s medical capabilities, they attached it to a robotic arm, where it successfully identified three lumps embedded in a large silicone pad, mimicking a doctor’s examination technique. While on the robotic arm, the finger also effectively located an artery on a participant’s wrist and measured their pulse.
“Humans naturally gauge the stiffness of different objects by simply applying pressure with their fingers,” the authors explain. “In a similar manner, since the [device] can sense both the bending deformation and the force at its fingertip, it can assess stiffness analogous to that of the human hand merely through pressing an object.”
In addition to measuring pulses and analyzing simulated lumps, the researchers discovered that the robotic finger could type “like a human,” successfully spelling out the word “hello.”
By incorporating additional sensors to enhance flexibility in the robotic finger’s joints, thus enabling movement in multiple directions like a human finger, the device could soon be ready to conduct thorough and efficient medical examinations, the authors conclude.
“We aspire to develop an intelligent, flexible hand paired with a sensor-equipped, artificial muscle-driven robotic arm to replicate the unmatched capabilities and precise manipulations of human hands,” remarked Wang.
